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Analysing debranching techniques in Frozen Elephant Trunk procedures: a narrative literature review.Cardiovascular Diagnosis and Therapy Apr 2023Since 2003, the Frozen Elephant Trunk (FET) technique has attained rising popularity for treating extensive aortic arch pathologies such as acute and chronic aortic... (Review)
Review
BACKGROUND AND OBJECTIVE
Since 2003, the Frozen Elephant Trunk (FET) technique has attained rising popularity for treating extensive aortic arch pathologies such as acute and chronic aortic dissection, as well as thoracic aortic aneurysm. Conventionally, the FET procedure included a complete resection of the aortic arch and, subsequently, a distal aortic anastomosis of the prosthetic part of the hybrid graft in arch zone 3. Simultaneous to the introduction of the FET technique, the traditional Elephant Trunk technique was simplified by adding debranching techniques which allows for proximalization of the distal aortic anastomosis. Nowadays, modern concepts of aortic arch surgery combine the FET technique with proximalization of the distal anastomosis in arch zone 2 or further proximal, achieved by using different debranching techniques. This review describes different debranching techniques to facilitate arch reconstruction, and aims to critically assess the outcomes and potential clinical advantages of proximalization using debranching in FET surgery.
METHODS
We conducted a search using the PubMed and Google Scholar electronic databases to evaluate published outcomes of different debranching techniques. An overview of the data synthesis of 21 included studies is reported.
KEY CONTENT AND FINDINGS
Most studies report numeric, but not statistically significant improved outcomes after debranching in FET surgery for mortality, neurological complications, spinal cord injury, kidney failure, bowel ischemia and recurrent nerve palsy. Some studies report statistically significant improved results in isolated endpoints such as neurological, bowel ischemia, and recurrent nerve palsy. Most studies report debranching to be technically easier, but this is difficult to objectively assess and measure.
CONCLUSIONS
There is an improved numeric outcome of different debranching techniques with proximalization of the distal anastomosis, but without reaching statistical significance. This review shows marked heterogeneity across included studies and highlights the scarce use of existing guidelines in clinical research of open aortic arch surgery as proposed by the International Aortic Arch Surgery Study Group. Furthermore, this review demonstrates the urgent need for multicenter registries or studies to be able to compare the outcome of different surgical techniques for various aortic arch pathologies.
PubMed: 37583690
DOI: 10.21037/cdt-22-502 -
International Journal of Colorectal... Feb 2007Colorectal cancer (CRC) ranks as the fourth most frequently diagnosed cancer worldwide. CRCs that arise proximally or distally to the splenic flexure show differences in...
BACKGROUND AND AIMS
Colorectal cancer (CRC) ranks as the fourth most frequently diagnosed cancer worldwide. CRCs that arise proximally or distally to the splenic flexure show differences in epidemiologic incidence, morphology, and molecular alterations, suggesting the existence of two categories of CRC based on the site of origin. The aim of the present work is to investigate the histological and molecular differences between CRCs located proximally and distally to the splenic flexure, and their potential involvement in tumor prognosis and therapeutic strategies.
METHODS
We evaluated 120 patients affected by sporadic CRC for clinicopathologic features, microsatellite instability (MSI), loss of heterozygosity (LOH) of chromosomes 18q, 8p, and 4p; they were also investigated for hMlh1, hMsh2, Fhit, p27, and Cox-2 immunostaining.
RESULTS
The mucinous histotype was more frequent in the proximal than in the distal CRCs (p<0.004). The frequency of MSI phenotype was higher in proximal than in distal tumors (p<0.001); moreover, reduced or absent hMlh1, Fhit, p27 immunohistochemical expressions were more frequent in proximal than in distal tumors (p<0.001 and 0.01 for p27). In contrast, the frequency of LOH in 18q was higher in distal than in proximal tumors (p=0.002). No significant differences were observed between proximal and distal tumors in the frequency of LOH in 8p and altered expression of hMsh2 and p53 protein.
CONCLUSION
These different features may reflect different genetic pathways of carcinogenesis and support the hypothesis of a different mechanism of cancer development between the proximal and the distal colon, with potential implications in the therapeutic approach.
Topics: Acid Anhydride Hydrolases; Adaptor Proteins, Signal Transducing; Aged; Biomarkers, Tumor; Cell Transformation, Neoplastic; Colorectal Neoplasms; Cyclooxygenase 2; Female; Humans; Immunohistochemistry; Loss of Heterozygosity; Male; Microsatellite Instability; MutL Protein Homolog 1; MutS Homolog 2 Protein; Neoplasm Proteins; Nuclear Proteins; Proliferating Cell Nuclear Antigen; Survival Analysis
PubMed: 17021745
DOI: 10.1007/s00384-006-0093-x -
Cureus Mar 2018Acute esophageal necrosis (AEN) is a particularly rare syndrome with an incidence of only 0.1-0.28%, whose appearance is notable for proximal extensions of black,...
Acute esophageal necrosis (AEN) is a particularly rare syndrome with an incidence of only 0.1-0.28%, whose appearance is notable for proximal extensions of black, necrotic appearing mucosa extending proximally in the esophagus and abruptly interrupted at the gastroesophageal junction. In this case series, we explore the cases of two males: one middle-aged and one elderly, who after presenting with emesis, were found to have acute esophageal necrosis on esophagogastroduodenoscopy.
PubMed: 29850386
DOI: 10.7759/cureus.2391 -
Journal of Special Operations Medicine... 2017In practice, the distance between paired tourniquets varies with unknown effects.
BACKGROUND
In practice, the distance between paired tourniquets varies with unknown effects.
METHODS
Ratcheting Medical Tourniquets were applied to both thighs of 15 subjects distally (fixed location) and proximally (0, 2, 4, 8, 12cm gap widths, randomized block). Applications were pair, single distal, single appropriate proximal. Tightening ended one-ratchet tooth advance past Doppler-indicated occlusion. Pairs had alternating tightening starting distal.
RESULTS
Occlusion pressures were higher for: each single than respective individual pair tourniquet, each pair distal than respective pair proximal, and each single distal than respective single proximal (all p < .0001). Despite thigh circumference increasing proximally, occlusion pressures were lower with proximal tourniquet involvement (pair or single, p < .0001). Occlusion losses before 120 seconds occurred most frequently with pairs (0cm 4, 2cm 4, 4cm 6, 8cm 7, 12cm 5 for 26 of 150), in increasing frequency with increasingly proximal singles (0cm 0, 2cm 1, 4cm 1, 8cm 2, 12cm 6 for 10 of 150, p < .0001 for trend), and least with single distal (2 of 150, p < .0001). Paired tourniquets required fewer ratchet advances per tourniquet (pair distal 5 ± 1, pair proximal 4 ± 1, single distal 6 ± 1, single proximal 6 ± 1). Final ratchet tooth advancement pressure increases (mmHg) were greatest for singles (distal 61 ± 10, proximal 0cm 53 ± 7, 2cm 51 ± 9, 4cm 50 ± 7, 8cm 45 ± 7, 12cm 36 ± 7) and least in pairs (distal 41 ± 8, proximal 32 ± 7) with progressively less pair interaction as distance increased (pressure change for the pair tourniquet not directly advanced: 0cm 13 ± 4, 2cm 10 ± 4, 4cm 6 ± 3, 8cm 1 ± 2, 12cm -1 ± 2).
CONCLUSIONS
Occlusion pressures are lower for paired than single tourniquets despite variable intertourniquet distances. Very proximal placement has a pressure advantage; however, pairs and very proximal locations may be less likely to maintain occlusion. Increasingly proximal placements also increase tissue at risk; therefore, distal placements and minimal intertourniquet distances should still be recommended.
Topics: Adult; Equipment Design; Female; Healthy Volunteers; Hemostatic Techniques; Humans; Male; Middle Aged; Pressure; Regional Blood Flow; Thigh; Tourniquets; Ultrasonography, Doppler; Young Adult
PubMed: 29256192
DOI: 10.55460/AQ40-J458 -
The Analyst Oct 2017Chemosensors for the detection of phosphate-containing biological species are in high need. Detection of proximally phosphorylated sites of PP and those found in...
Chemosensors for the detection of phosphate-containing biological species are in high need. Detection of proximally phosphorylated sites of PP and those found in peptides and proteins has been demonstrated using chemosensors containing pyrene, as a fluorescent reporter, and a Zn-chelate, as a phosphate-binding group. Using these sensors, detection of proximal phosphate groups is afforded by binding of at least two of the sensor molecules to the adjacent phosphates, via the Zn centres, leading to excimer formation between the pyrene groups and the corresponding shift in emission from 376 to 476 nm. Although several reports of this chemosensor class have been made, no detailed studies of selectivity of these sensors among major phosphate targets have been reported. In this study, a library of this class of chemosensors, termed ProxyPhos, which contained various linkers and Zn-chelating groups (i.e. DPA, cyclen and cyclam), was prepared and the effects of structural variation on the sensing efficiency and selectivity were evaluated among proximally phosphorylated peptides, proteins, nucleotides, P and PP. As a result of this study, we have identified ProxyPhos library members that are most suitable for the detection of proximally phosphorylated peptides, PP, UTP, and a DpYD peptide motif, and have generally provided a foundation for the selection of ProxyPhos chemosensors for further development of specific biologically relevant assays. The broad utility of ProxyPhos is further supported by the demonstrated lack of these sensors' cytotoxicity, ability to rapidly permeate into live and fixed cells and compatibility with gel staining methods.
Topics: Biosensing Techniques; Molecular Structure; Peptides; Phosphates; Phosphorylation; Structure-Activity Relationship; Zinc
PubMed: 28930308
DOI: 10.1039/c7an00722a -
Spine Nov 2007A retrospective comparison study. (Comparative Study)
Comparative Study
STUDY DESIGN
A retrospective comparison study.
OBJECTIVE
To compare the postoperative proximal junctional change and revision prevalence as influenced by 3 different proximal levels after adult lumbar deformity instrumented fusion from the distal thoracic/upper lumbar spine (T9-L2) to L5 or S1.
SUMMARY OF BACKGROUND DATA
Few comparative studies on postoperative sagittal plane change and revision prevalence as influenced by 3 different proximal levels after adult lumbar deformity instrumented fusion from the distal thoracic/upper lumbar spine (T9-L2) to L5 or S1 have been published. Many surgeons have hypothesized that stopping proximally in the upper lumbar spine (L1 or L2) or the thoracolumbar junction (T11 or T12) would lead to a high percentage of rapid proximal degeneration, kyphosis, and decompensation because of the concentration of stress on these relatively mobile segments. Therein, many surgeons have felt it is unsafe to stop at these regions of the spine and it is better to always stop proximally at T9 or T10.
METHODS
A clinical and radiographic assessment in addition to revision prevalence of 125 adult lumbar deformity patients (average age 57.1 year) who underwent long (average 7.1 vertebrae) segmental posterior spinal instrumented fusion from the distal thoracic/upper lumbar spine (T9-L2) to L5 or S1 with a minimum 2-year follow-up (2-19.8 year follow-up) were compared as influenced by T9-T10 (group 1, n = 37), T11-T12 (group 2, n = 49), and L1-L2 (group 3, n = 39) proximal fusion levels. The revision prevalence and sagittal Cobb angle change at the proximal junction after surgery were compared.
RESULTS
Three groups demonstrated nonsignificant differences in the prevalence of proximal junctional kyphosis (group 1 51% vs. group 2 55% vs. group 3 36%, P = 0.20) and revision (group 1 24% vs. group 2 24% vs. group 3 26%, P = 0.99) at the ultimate follow-up. Subsequent proximal junctional angle and sagittal vertical axis changes between the ultimate follow-up and preoperative (P = 0.10 and 0.46 respectively) were not significantly different. The SRS total and all subscale outcomes scores among the 3 groups did not demonstrate significant differences (P > 0.50).
CONCLUSION
Three different proximal fusion levels did not demonstrate significant radiographic and clinical outcomes or revision prevalence after surgery. Therefore the more distal proximal fusion level at a neutral and stable vertebra may be satisfactory.
Topics: Adult; Aged; Female; Follow-Up Studies; Humans; Kyphosis; Lumbar Vertebrae; Male; Middle Aged; Postoperative Complications; Prevalence; Radiography; Reoperation; Retrospective Studies; Sacrum; Scoliosis; Spinal Fusion; Spine; Thoracic Vertebrae; Treatment Outcome
PubMed: 18007240
DOI: 10.1097/BRS.0b013e31815a5a9d -
Neurologia Medico-chirurgica Nov 1993A 38-year-old male presented with vertebral artery dissecting aneurysm manifesting as subarachnoid hemorrhage. An attempt at trapping the aneurysm failed, so the...
A 38-year-old male presented with vertebral artery dissecting aneurysm manifesting as subarachnoid hemorrhage. An attempt at trapping the aneurysm failed, so the vertebral artery could only be clipped proximally. Rebleeding occurred, resulting in death, probably due to excessive length of the dissection requiring thrombosis and/or retrograde dissection due to back pressure from the contralateral vertebral artery.
Topics: Adult; Aortic Dissection; Humans; Intracranial Aneurysm; Male; Recurrence; Subarachnoid Hemorrhage; Vertebral Artery
PubMed: 7506814
DOI: 10.2176/nmc.33.765 -
Developmental Dynamics : An Official... Dec 2001The proximal-distal patterning of lung epithelium involves a complex series of signaling and transcriptional events resulting in the programmed differentiation of highly...
The proximal-distal patterning of lung epithelium involves a complex series of signaling and transcriptional events resulting in the programmed differentiation of highly specialized cells for gas exchange and surfactant protein expression essential for postnatal lung function. The BMP signaling pathway has been shown to regulate cellular differentiation in the lung as well as other tissues. In this report, we show that the can family of related BMP antagonists, including gremlin, cer-1, PRDC, and Dan are expressed in the lung during embryonic development with gremlin expression observed in the proximal airway epithelium. The role of gremlin in lung development was explored by overexpressing it in the distal lung epithelium of transgenic mice using the human SP-C promoter. SP-C/gremlin transgenic mice exhibited a disruption of the proximal-distal patterning found in the airways of the mammalian lung. Expanded expression of the proximal epithelial cell markers CC10 and HFH-4 (Foxj1) was observed in the distal regions of transgenic lungs. Furthermore, smooth muscle alpha-actin expression was observed surrounding the distal airways of SP-C/gremlin mice, indicating a proximalization of distal lung tubules. These data suggest that gremlin plays an important role in lung morphogenesis by regulating the proximal-distal patterning of the lung during development.
Topics: Animals; Body Patterning; Bone Morphogenetic Proteins; Cytokines; Embryo, Mammalian; Embryonic and Fetal Development; Humans; Intercellular Signaling Peptides and Proteins; Lung; Mice; Mice, Transgenic; Muscle, Smooth; Proteins; Proteolipids; Pulmonary Surfactants; Transcription, Genetic
PubMed: 11748835
DOI: 10.1002/dvdy.1231 -
Clinical Orthopaedics and Related... Jan 1994The proximal femur is frequently structurally deficient in revision hip arthroplasty, and makes obtaining prosthesis stability more difficult. Between 1984 and 1990, 174...
The proximal femur is frequently structurally deficient in revision hip arthroplasty, and makes obtaining prosthesis stability more difficult. Between 1984 and 1990, 174 patients were treated with revision total hip arthroplasty, performed by a standardized surgical technique, using cortical onlay strut allografts to restore the structural integrity of the femur, and a calcar replacement proximally porous-coated femoral prosthesis, composed of titanium alloy. The grafts united 98% of the time, and showed evidence of revascularization, and in some cases, complete incorporation. To date, six have been revised for femoral failure. Successful reconstruction of the deficient femur after failed total hip arthroplasty is dependent on several factors: the revision prosthesis must be stable, the deficient femoral bone stock must be augmented, and load must be transferred to the proximal femur so that the future proximal femoral resorption is minimized. The host femur and allograft will respond physiologically to load bearing, and the graft increases bone quantity and quality. The prosthesis must be supported primarily on host bone; the graft may enhance prosthetic support, but can never be used for primary prosthetic support when using uncemented revision prostheses.
Topics: Aged; Arthroplasty; Bone Transplantation; Female; Femur; Hip Prosthesis; Humans; Male; Middle Aged; Osseointegration; Prosthesis Design; Prosthesis Failure; Reoperation; Transplantation, Homologous
PubMed: 8118966
DOI: No ID Found -
Arthroplasty Today Jun 2022[This corrects the article DOI: 10.1016/j.artd.2020.09.007.].
Erratum to "Diagnosis of and Early Revision Surgery for Biological Fixation Failure Due to Proximal-Distal Mismatch of Proximally Coated Tapered Cementless Stem" [Arthroplasty Today 6 (2020) 914-918].
[This corrects the article DOI: 10.1016/j.artd.2020.09.007.].
PubMed: 35774872
DOI: 10.1016/j.artd.2022.06.001